1. Field of the Invention
This invention relates to an image processing apparatus and an image processing method. More particularly, it relates to an image processing apparatus and an image processing method for dividing a document image to produce images of individual image areas or dividing a document image formed by assigning a plurality of pages to produce individual images of the pages.
2. Description of the Related Art
Image forming apparatus such as printers include those having an N in 1 printing feature of arranging the printing data of a plurality of pages received from a computer so as to print images of reduced sizes of the pages on a single sheet of recording paper. In other words, it is possible to print N pages on a single sheet of recording paper by assigning the data of the N pages to the sheet of recording paper by means of the N in 1 printing feature. There may be cases where the user of such an N in 1 printing feature wants to take in a document image formed by such space assignment by means of the N in 1 printing feature and reuse the electronic data of each of the pages, or each of the page images, in a condition before it is assigned to a sheet of recording paper with the other pages.
Additionally, there may be cases where the user wants to reuse the electronic data of each photograph, character or graphic on a sheet of document, or a document image, as electronic data of an image region.
Jpn. Pat. Appln. Laid-Open Publication No. 2002-215380 discloses a technique of dividing a document image formed by space assignment into individual page images. Jpn. Pat. Appln. Laid-Open Publication No. 2003-87562 discloses a technique of dividing a sheet of document image into images of image regions. However, the techniques disclosed in the above-cited patent documents are not developed by taking the easiness of viewing of the page images produced as a result of dividing the document image or the images of image regions and the data size into consideration. Therefore, the images produced by dividing a document image can often be short of resolution and it is difficult for the viewer to read small characters contained in the images produced by the division. Additionally, when the document image is partly printed in color, all the images produced by the division are preserved as full color images. Then, the size of the full color images produced by the division has to be made unnecessarily large.
If the images produced by such a division are not objects of easy viewing, the value of the images produced by the division is damaged when they are reused. If the images produced by such a division have an unnecessarily large size, a large memory region has to be used to preserve them and it takes a long processing time when they are reused.